public class DataSourceSingletonTest {
    public static void main(String[] args) {
        Thread t1=new Thread(()->{
            System.out.println(DataSourceSingleton2.getInstance());
        });

        Thread t2=new Thread(()->{
            System.out.println(DataSourceSingleton2.getInstance());
        });
        t1.start();
        t2.start();
    }
}
